Comparative study of the antioxidant effect of ardisin and epigallocatechin gallate in rat hepatocytes exposed to benomyl and 1-nitropyrene.

The objective of this study was to compare the antioxidant effect of ardisin and epigallocatechin 3-O-gallate (EGCG) in hepatocytes exposed to either benomyl or 1-nitropyrene (1-NP). Rat hepatocytes were incubated in a serum-free medium with non-cytotoxic concentrations of either ardisin (0.27 microg/ml) or EGCG (3 microg/ml), and with either benomyl (35 microg/ml) or 1-NP (0.25 microg/ml). The level of malondialdehyde (MDA) as a marker of lipid peroxidation was determined, as well as the content of glutathione (GSH) and the activities of glutathione peroxidase (GPx) and glutathione reductase (GR). In comparison to the control, the concentration of GSH improved 282% (P<0.05) and 260% (P<0.05) after the cells were pre-incubated with ardisin or EGCG and then exposed to benomyl, respectively. The activity of GPx decreased 55% with ardisin (P<0.05) and 51% with EGCG (P<0.05), and MDA decreased 7% and 23% (P<0.05) with the same treatments. The concentration of GSH also improved when the cells were incubated with either EGCG (49%, P<0.05) or ardisin (83%, P<0.05) simultaneously with 1-NP, relative to 1-NP alone. Moreover, ardisin decreased MDA formation by 65% (p<0.05), and enhanced the activity of GR by 137% (P<0.05). These results suggest that ardisin is a better suppressor of lipid peroxidation induced by benomyl and 1-NP than EGCG. It is concluded that ardisin and EGCG are potent antioxidants that can afford protection against free radical mediated diseases.